I have a 2017 Highlander with the Auto Start/Stop. Currently, it will sometimes go completely dead while in park or when idling, like at a stop light. Completely dead meaning zero electricity - no lights, no ability to unlock doors, no ability to roll down windows, nothing. This will last 2 seconds to 15 minutes. The only codes it throws is P0116 and P011B, but sometimes it will happen with no codes. My mechanic is stumped. My suspicion is that the start/stop is malfunctioning and, for now, I turn off the Auto Start/Stop every time I get in the vehicle.
More backstory: starting in March I was letting the car sit for weeks at a time due to quarantining. Many times, the battery would be dead when I got in and we would have to jump it. Auto shop tested the battery and found it to be fine. No codes. It got progressively worse until it might only be sitting for 12 hours and need to be jumped, until it eventually became so dead it could not be jumped. The battery was then deemed bad (tested bad and could not be charged) and had to be replaced. So, these new 'dying while idling' issues are happening with a 2 month old battery. The connections have been looked at, the new battery tested.
More specific stories on recent 'deaths': I had driven 2 hours straight and was in park in a parking lot, when the electricity cut out completely for almost 15 minutes. I did nothing to make it come back on other than test the start button every few minutes. It then worked fine the rest of the day. A couple days after that, I was idling in a drive-through when everything cut off for maybe 2 seconds, and then came back on again. After that, the P0116 and P011B codes came up and the dash flashed with "check engine/visit your dealer/Check AWD system" and it was fine the rest of the day. I have been idling at at stop light and it cut out for 2 minutes, which was very unnerving and caused me to hear many people's horns and selective fingers.
I have read about start/stop creating a slow drain on the battery and causing some people to have to repeatedly replace batteries until they installed the aftermarket disable switch. I have also seen that the 2020 start/stop has been recalled. The only common thread to when it dies is that it is a time when the auto start/stop might logically cut the engine. Instead, it cuts EVERYTHING (maybe?). I have not taken it to my local dealership for this, as they are notoriously awful to deal with. Has anyone else experienced this or have any other ideas to chase? Thanks in advance!
More backstory: starting in March I was letting the car sit for weeks at a time due to quarantining. Many times, the battery would be dead when I got in and we would have to jump it. Auto shop tested the battery and found it to be fine. No codes. It got progressively worse until it might only be sitting for 12 hours and need to be jumped, until it eventually became so dead it could not be jumped. The battery was then deemed bad (tested bad and could not be charged) and had to be replaced. So, these new 'dying while idling' issues are happening with a 2 month old battery. The connections have been looked at, the new battery tested.
More specific stories on recent 'deaths': I had driven 2 hours straight and was in park in a parking lot, when the electricity cut out completely for almost 15 minutes. I did nothing to make it come back on other than test the start button every few minutes. It then worked fine the rest of the day. A couple days after that, I was idling in a drive-through when everything cut off for maybe 2 seconds, and then came back on again. After that, the P0116 and P011B codes came up and the dash flashed with "check engine/visit your dealer/Check AWD system" and it was fine the rest of the day. I have been idling at at stop light and it cut out for 2 minutes, which was very unnerving and caused me to hear many people's horns and selective fingers.
I have read about start/stop creating a slow drain on the battery and causing some people to have to repeatedly replace batteries until they installed the aftermarket disable switch. I have also seen that the 2020 start/stop has been recalled. The only common thread to when it dies is that it is a time when the auto start/stop might logically cut the engine. Instead, it cuts EVERYTHING (maybe?). I have not taken it to my local dealership for this, as they are notoriously awful to deal with. Has anyone else experienced this or have any other ideas to chase? Thanks in advance!
